June 15th is the next time that personal instalments are due, and the amount is still based on your 2016 return. The payment due September 15th will be the first one based on the 2017 taxation year. Corporations are supposed to make a monthly payment of their instalments. Annual filers for HST are supposed to be paying quarterly as well. So far, CRA has not asked quarterly HST filers to pay monthly.
Why should you pay? These amounts are instalments, not tax, if you don’t owe the money you will get it back. If you do not pay your instalments, then CRA can charge you instalment interest. There is an exception to this being that if you don’t pay and you don’t owe, then CRA can’t charge the money. However, most of us are not psychic, so figuring out if you are going to owe income tax is not something you can do until the time has passed and the returns prepared. Pay your instalments and avoid interest and penalties. We all pay enough tax.